Various ureido substituted acetamidopenicillins are disclosed as possessing useful antibacterial activity by Fosker in U.S. Pat. No. 3,352,851, Erickson in U.S. Pat. No. 3,720,664, and Welch et al. in U.S. Pat. No. 3,720,665. Also disclosed as possessing useful antibacterial activity are various substituted ureido containing penicillins such as those disclosed by Ferres et al. in U.S. Pat. Nos. 3,923,788; 3,926,960; 3,935,189; 3,935,192; 3,957,759; and 3,962,216; by Disselnkotter et al. in U.S. Pat. Nos. 3,933,795; 3,936,442; 3,939,149; and 3,959,258; by Schrock et al. in U.S. Pat. No. 3,923,789 and by Murakami et al. in U.S. Pat. No. 3,939,150.